Unlocked Quadband Dual Sim Android 4.1 OS 4.7 Inch Capacitive Touch Screen 3G Smart Phone - AT&T, T-mobile, H20, GSM networks (White) by Mango Natural Frequency: GSM (2G) 850/900/1800/1900MHZ WCDMA (3G) 2100MHZ CPU: Media Tek MTK6577 4GB ROM+512MB RAM extend to 32GB max OS: Android 4.1 Dual camera, Dual SIM, Dual standby